Lexus Division unveiled its new LS 460 flagship luxury sedan that arrives in dealerships this fall, with standard and long-wheelbase editions, a hybrid version and a new F-Sport trim level with improved handling dynamics.

Despite its sheet metal changes, the car is actually little changed underneath. Its 4.6-liter V8 engine and eight-speed transmission are basically carryover, at a time when luxury brands are using powertrain technology as a differentiating ploy.

Also, the car's dimensions are almost identical--the only change is an additional inch in overall length for both base and long-wheelbase editions.

Lexus released details about the vehicle late Monday.

Getting the new LS right is crucial for Lexus. When the current model came out six years ago, it easily outsold the Mercedes-Benz S-class and BMW 7-series in its first full year of sales.

But the resurgence of the German marques has taken a chunk out of Lexus. Even before last year's earthquake crimped Lexus production, the BMW and Mercedes top models had pulled even with the Lexus flagship.

During the first six months, Lexus sold 3,036 LS vehicles in the United States--down 28 percent from the same period last year. BMW sold 5,604 7-series vehicles for a 3-percent gain while Mercedes sold 5,510 S-class units, a drop of 1 percent. The U.S. market, as a whole, rose 15 percent.

New features

The re-engineered LS 460 and LS 460L will be available in rear-wheel and all-wheel drive versions. The newly added F-Sport model comes with a Torsen limited slip differential, Brembo brakes and 19-inch wheels.

The engine gains a few horsepower, with zero-to-60-mph arriving in 5.4 seconds, and a 14-second quarter mile time.

While the suspension is also carryover, it features new frequency-dependent shock absorbers for a more responsive ride. Steering is described as having more accuracy and turn-in response, while the brakes have more pedal feel, Lexus says.

On the safety side, the LS 460 has a collision avoidance system that, at speeds below 24 mph, will bring the car to a halt if it detects a possible accident. The safety system also has blind-spot monitoring, lane departure warning sensors and a reverse-gear cross traffic alert.

Inside, 14 temperature sensors will ensure the automatic climate control is accurate. Interior lighting is entirely LED. The 12.3-inch split display screen from the GS sedan makes another appearance in the LS.